Evaluate $3+(-h)+(-4)$ where $h = -7$.
Solution: Let's substitute ${h = -7}$ into the expression. $\begin{aligned} &\phantom{=} 3+(-{h})+(-4) \\\\ &= 3+\left(-{\left(-7\right)}\right)+\left(-4\right) \end{aligned}$ $\begin{aligned} &= 3+7-4 \\\\ &=10-4 \end{aligned}$ $=6$